U.S. patent application number 15/097257 was filed with the patent office on 2017-10-12 for dye-sensitized solar panel.
The applicant listed for this patent is KING SAUD UNIVERSITY. Invention is credited to MANAL AHMED GASMELSEED AWAD, AWATIF AHMED HENDI, NAWAL AHMAD ABDU MADKHALI, KHALID MUSTAFA OSMAN ORTASHI.
Application Number | 20170294270 15/097257 |
Document ID | / |
Family ID | 59998840 |
Filed Date | 2017-10-12 |
United States Patent
Application |
20170294270 |
Kind Code |
A1 |
AWAD; MANAL AHMED GASMELSEED ;
et al. |
October 12, 2017 |
DYE-SENSITIZED SOLAR PANEL
Abstract
A dye-sensitized solar panel includes a titanium nanoparticle
layer and a plant-derived photo-sensitizer supported on the
titanium nanoparticle layer. The photo-sensitizer can be extracted
from chard (B. vulgaris subsp. cicla), and the titanium
nanoparticle layer includes titanium nanoparticles synthesized
using henna (Lawsonia inermis). The titanium nanoparticle layer
can, in addition to titanium nanoparticles, include zinc oxide
nanoparticles.
Inventors: |
AWAD; MANAL AHMED GASMELSEED;
(RIYADH, SA) ; HENDI; AWATIF AHMED; (RIYADH,
SA) ; ORTASHI; KHALID MUSTAFA OSMAN; (RIYADH, SA)
; MADKHALI; NAWAL AHMAD ABDU; (RIYADH, SA) |
|
Applicant: |
Name |
City |
State |
Country |
Type |
KING SAUD UNIVERSITY |
RIYADH |
|
SA |
|
|
Family ID: |
59998840 |
Appl. No.: |
15/097257 |
Filed: |
April 12, 2016 |
Current U.S.
Class: |
1/1 |
Current CPC
Class: |
H01G 9/2036 20130101;
H01G 9/2031 20130101; Y02P 70/50 20151101; Y02E 10/549 20130101;
H01G 9/2059 20130101; Y02E 10/542 20130101; H01L 51/0093 20130101;
Y02P 70/521 20151101 |
International
Class: |
H01G 9/20 20060101
H01G009/20; H01L 51/00 20060101 H01L051/00; H01G 9/00 20060101
H01G009/00 |
Claims
1. A dye-sensitized solar panel, comprising: a first transparent
substrate having opposed inner and outer surfaces; a working
electrode mounted on the inner surface of the first transparent
substrate, the working electrode comprising: a metal electrode; a
titanium nanoparticle layer; and an organic photosensitizing dye
supported on the titanium nanoparticle layer, wherein the
photosensitizing dye includes B. vulgaris subsp. cicla dye; a
second transparent having opposed inner and outer surfaces; a
counter electrode mounted on the inner surface of the second
transparent substrate, the counter electrode comprising a
conductive layer; and an electrolyte sandwiched between the working
electrode and the counter electrode.
2. The dye-sensitized solar panel as recited in claim 1, wherein
said first and second transparent substrates each comprise
fluorine-doped tin oxide.
3. The dye-sensitized solar panel as recited in claim 2, wherein
said conductive layer of said counter electrode comprises
graphite.
4. The dye-sensitized solar panel as recited in claim 3, wherein
said electrolyte comprises lemon juice.
5. The dye-sensitized solar panel as recited in claim 1, wherein
said titanium nanoparticle layer further includes zinc oxide
nanoparticles.
6. The dye-sensitized solar panel as recited in claim 1, wherein
said titanium nanoparticles are synthesized using a Lawsonia
inermis dye as a reducing agent.
7. The dye-sensitized solar panel as recited in claim 1, wherein
the metal electrode has a resistance less than 30.OMEGA..
8. A method of making a dye-sensitized solar panel, comprising the
steps of: securing a metal electrode to an inner surface of a first
transparent substrate; coating the metal electrode with a titanium
nanoparticle layer to form a coated first substrate, the titanium
nanoparticle layer including titanium nanoparticles synthesized
using Lawsonia inermis extract as a reducing agent; soaking the
coated first substrate in an organic photosensitizing dye to adsorb
the organic photosensitizing dye therein, the photosensitizing dye
comprising B. vulgaris subsp. cicla dye; mounting a counter
electrode to an inner surface of a second transparent substrate;
and sandwiching an electrolyte between the working electrode and
the counter electrode.
9. The method of making a dye-sensitized solar panel as recited in
claim 8, wherein the step of soaking the coated first substrate in
the organic photosensitizing dye comprises soaking the coated first
substrate in the organic photosensitizing dye for 24 hours.
10. The method of making a dye-sensitized solar panel as recited in
claim 8, wherein the step of mounting the counter electrode to the
inner surface of the second transparent substrate comprises
mounting a graphite layer to the inner surface of the second
transparent substrate.
11. The method of making a dye-sensitized solar panel as recited in
claim 8, wherein the step of sandwiching the electrolyte between
the working electrode and the counter electrode comprises
sandwiching lemon juice between the working electrode and the
counter electrode.
12. The method of making a dye-sensitized solar panel as recited in
claim 8, wherein the titanium nanoparticle layer further includes
zinc oxide nanoparticles synthesized using Lawsonia inermis extract
as a reducing agent.
13. The method of making a dye-sensitized solar panel as recited in
claim 8, further comprising the steps of: blending leaves of B.
vulgaris subsp. cicla in water; centrifuging the blended leaves of
B. vulgaris subsp. cicla in the water; and extracting the B.
vulgaris subsp. cicla dye.
Description
BACKGROUND OF THE INVENTION
1. Field of the Invention
[0001] The present invention relates to solar cells, solar panels
and the like, and particularly to a dye-sensitized solar panel
including an extract of chard (B. vulgaris subsp. cicla).
2. Description of the Related Art
[0002] A dye-sensitized solar cell (DSSC) is a type of solar cell
belonging to the group of thin film solar cells. The dye-sensitized
solar cell has a number of attractive features, such as its
relatively easy and low-cost manufacture, typically by conventional
roll-printing techniques. Most dye-sensitized solar cells are also
semi-flexible and semi-transparent, offering a variety of uses
which are typically not applicable to glass-based systems.
[0003] The performance of the DSSC is mainly based on the dye
sensitizer, which acts as an electron pump to transfer the sunlight
energy into electron potential. Natural photo-sensitizers have
become a viable alternative to other sensitizers because of their
low cost, abundance, and little or no associated environmental
threat. Intensive research efforts have been directed toward the
application of several highly efficient light-harvesting
photosynthetic pigment-protein complexes, including reaction
centers, photosystem I (PSI), and photosystem II (PSII), as key
components in the light-triggered generation of fuels or electrical
power. Thus, a dye-sensitized solar panel with a natural dye
solving the aforementioned problems is desired.
SUMMARY OF THE INVENTION
[0004] A dye-sensitized solar panel includes a titanium
nanoparticle layer and a plant-derived photo-sensitizer supported
on the titanium nanoparticle layer. The photo-sensitizer can be
extracted from chard (B. vulgaris subsp. cicla), and the titanium
nanoparticle layer includes titanium nanoparticles synthesized
using henna (Lawsonia inermis). The titanium nanoparticle layer
can, in addition to titanium nanoparticles, include zinc oxide
nanoparticles.
[0005] These and other features of the present invention will
become readily apparent upon further review of the following
specification and drawing.
BRIEF DESCRIPTION OF THE DRAWINGS
[0006] The sole drawing FIGURE is a side view in section of a
dye-sensitized solar panel with an organic chromophore according to
the present invention.
[0007] Similar reference characters denote corresponding features
consistently throughout the attached drawing.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS
[0008] A dye-sensitized solar panel 10 includes a titanium
nanoparticle layer and a plant-derived photo-sensitizer supported
on the titanium nanoparticle layer. The photo-sensitizer can be
extracted from chard (B. vulgaris subsp. cicla), and the titanium
nanoparticle layer includes titanium nanoparticles synthesized
using henna (Lawsonia inermis). The titanium nanoparticle layer
can, in addition to titanium nanoparticles, include zinc oxide
nanoparticles. As shown in the sole FIGURE, the dye-sensitized
solar panel 10 can include first and second transparent substrates
12, 18, respectively, each having opposed inner and outer surfaces.
The first and second transparent substrates may be formed from any
type of transparent glass or other transparent material, such as
fluorine-doped tin oxide, as is well known in the construction of
dye-sensitized solar panels.
[0009] A working electrode is mounted on the inner surface 26 of
the first transparent substrate 12. The working electrode includes
a metal electrode 14 (with a resistance preferably less than
30.OMEGA.) and a titanium nanoparticle layer 16 formed thereon. The
titanium nanoparticle layer 16 includes titanium nanoparticles
synthesized using henna (Lawsonia inermis) dye or extract as a
reducing agent. A photosensitizer layer is also supported on the
titanium nanoparticle layer 16 which, as noted above, includes B.
vulgaris subsp. cicla dye.
[0010] As in a conventional dye-sensitized solar panel, a counter
electrode is mounted on the inner surface 28 of the second
transparent substrate 18. The counter electrode includes a metal
plate 20 formed on the inner surface 28 of the second transparent
substrate 18. The metal plate 20 can be coated with a layer of
graphite or the like. An electrolyte 22 is sandwiched between the
working electrode and the counter electrode, and the panel 10 is
preferably sealed with a suitable seal 24, gasket or the like to
prevent leakage of the electrolyte 22. The electrolyte may be any
suitable type of electrolyte used in the construction of
dye-sensitized solar panels, such as lemon juice or the like.
[0011] In order to prepare the henna (Lawsonia inermis) extract or
dye, Lawsonia inermis leaves were collected from the city of
Aldamer in the Republic of the Sudan. The leaves were thoroughly
washed with water to remove dust from their surfaces. 100 g of the
leaves were dried and ground, producing a henna powder. The henna
powder was soaked in 100 mL of warm distilled water and left for 24
hours. The solution was then filtered and used for the dye
solution. The dye solution had a dark red color.
[0012] The dye or extract obtained from the B. vulgaris subsp.
cicla was made by washing half of a conventional sized bag of B.
vulgaris subsp. cicla leaves, and then blending the leaves in
approximately 100 mL of water. The leaves were ground in the water
for between 5 and 10 minutes until the leaves were thoroughly
blended. The blended leaves in the water were then centrifuged at
9,000 rpm for 10 minutes to provide the B. vulgaris subsp. cicla
dye or extract. The B. vulgaris subsp. cicla dye is green in
color.
[0013] In order to synthesize the titanium nanoparticles, titanium
(IV) isopropoxide and the henna dye extract were mixed together at
a volume ratio of 1:2, respectively, under vigorous magnetic
stirring, yielding a red paste. The paste was dried at 60.degree.
C. for seven hours, and then at 400.degree. C., resulting in a red
powder of titanium nanoparticles. The dyed titanium nanoparticles
had an average diameter of 71.33 nm. Similarly, in order to
synthesize the zinc oxide nanoparticles, 0.1 M of zinc acetate was
dissolved in the henna extract and kept under constant and vigorous
magnetic stirring at 70.degree. C. until completely dissolved.
After complete dissolution of the zinc acetate, 0.1 M sodium
hydroxide (NaOH) aqueous solution was added under constant
high-speed stirring, drop by drop, yielding a red paste. The paste
was dried in an oven at about 400.degree. C., resulting in a powder
of zinc oxide nanoparticles. The zinc oxide nanoparticles had an
average diameter of 166.1 nm.
EXAMPLE 1
[0014] A control sample was prepared using titanium nanoparticles
synthesized with henna (Lawsonia inermis) extract as a reducing
agent, but without the B. vulgaris subsp. cicla dye sensitizer. The
titanium nanoparticles were prepared as a paste in nitric acid and
coated on a first transparent substrate, formed from fluorine-doped
tin oxide. A metal electrode was attached to the first transparent
substrate. The paste was left to dry, forming a titanium
nanoparticle layer. Small drops of lemon juice were then applied as
the electrolyte. A metal plate was coated with graphite (obtained
from a pencil) to form the counter electrode, which was mounted on
a second transparent substrate, also framed from fluorine-doped tin
oxide. The coated sides of the two substrates were brought
together, but offset so that uncoated glass extended beyond the
sandwich. The metal electrode did not completely cover inner
surface of the substrate. A seal was applied on all sides to
prevent leakage of the electrolyte.
[0015] The sample solar panels were exposed to light from a volt
lamp (emitting a mean intensity of 700 lux) and then tested for
current and voltage using a microvolt digital multimeter, such as
the Model 177 Microvolt DMM, manufactured by Keithley Instruments,
Inc. of Cleveland, Ohio. The solar panel was connected to a series
of potentiometers with resistance values ranging from 100.OMEGA. to
1000.OMEGA.. The microvolt digital multimeter measured current and
voltage for each load. The values for current and voltage were
calculated and measured for maximum current (I.sub.m), maximum
voltage (V.sub.m), open circuit voltage (V.sub.oc), and the short
circuit current (I.sub.sc), and these values were used to calculate
the fill factor (FF) and the overall energy conversion efficiency
(.eta.). The conversion efficiency (.eta.) is calculated as
.eta. = I m .times. V m input power .times. 100 % ##EQU00001##
and the fill factor (FF) is calculated as
FF = I m .times. V m I sc .times. V oc . ##EQU00002##
[0016] For the control sample, the maximum voltage was 0.083 V, the
maximum current was 0.025 A, the short circuit current was 0.1 A,
and the open circuit voltage was 0.12 V. Thus, for the control
sample without the B. vulgaris subsp. cicla chromophore dye, the
conversion efficiency was 2% and the fill factor was 0.0215.
EXAMPLE 2
[0017] In a second example, a sample solar panel was prepared using
the titanium nanoparticles synthesized using henna (Lawsonia
inermis) extract as a reducing agent and with the B. vulgaris
subsp. cicla dye sensitizer layer supported thereon. The titanium
nanoparticles were prepared as a paste in nitric acid and coated on
a first transparent substrate to which a metal electrode was
mounted. The first substrate was formed from fluorine-doped tin
oxide. The paste was left to dry, forming the titanium nanoparticle
layer. The coated first substrate with the titanium nanoparticle
layer was soaked in the B. vulgaris subsp. cicla dye for a period
of 24 hours for adsorption of sufficient dye onto the titanium
nanoparticle layer to form a sensitizer. The structure was then
rinsed with ethanol to remove any excess dye and, when dry, small
drops of lemon juice were applied as the electrolyte. A metal plate
was coated with graphite (obtained from a pencil) to form a counter
electrode, which was mounted on a second transparent substrate,
also formed from fluorine-doped tin oxide. The coated sides of the
two substrates were brought together, but offset so that uncoated
glass extends beyond sandwich. The metal electrode did not
completely cover inner surface of the substrate. A seal was applied
on all sides to prevent leakage of the electrolyte.
[0018] The sample solar panel was tested in a manner identical to
the control sample of Example 1. For the sample solar panel of
Example 2, the maximum voltage was 0.284 V, the maximum current was
0.025 A, the short circuit current was 0.4 A, and the open circuit
voltage was 0.245 V. Thus, for the sample solar panel with the B.
vulgaris subsp. cicla dye, the conversion efficiency was 67% and
the fill factor was 0.7245.
EXAMPLE 3
[0019] In a third example, a sample solar panel was prepared using
a composite of titanium nanoparticles synthesized with henna
(Lawsonia inermis) extract as a reducing agent and zinc oxide
nanoparticles synthesized with henna (Lawsonia inermis) extract as
a reducing agent, with the B. vulgaris subsp. cicla chromophore dye
supported thereon. 0.5 g of the titanium nanoparticles and the zinc
oxide nanoparticles were mixed together and ground in a pestle and
a few drops of nitric acid were added to form a paste.
[0020] The paste was coated on a first transparent substrate to
which a metal electrode was mounted. The first transparent
substrate was formed from fluorine-doped tin oxide. The paste was
left to dry, forming the composite nanoparticle layer. The coated
first substrate with the composite nanoparticle layer was soaked in
the B. vulgaris subsp. cicla dye for a period of 24 hours to adsorb
enough of the dye onto the composite nanoparticle layer to provide
a sensitizer. The structure was then rinsed with ethanol to remove
any excess dye and, when dry, small drops of lemon juice were
applied as the electrolyte. A metal plate was coated with graphite
(obtained from a pencil) to form the counter electrode, which was
mounted on the second transparent substrate, also formed from
fluorine-doped tin oxide. The coated sides of the two substrates
were brought together, but offset so that uncoated glass extended
beyond the sandwich. The metal electrode did not completely cover
inner surface of the substrate. A seal was applied on all sides to
prevent leakage of the electrolyte.
[0021] The sample solar panel was tested in a manner identical to
the samples of Example 1 and Example 2. For the sample solar panel
of Example 3, the maximum voltage was 0.445 V, the maximum current
was 0.021 A, the short circuit current was 0.16 A, and the open
circuit voltage was 0.3 V. Thus, for the sample solar panel with
the B. vulgaris subsp. cicla chromophore dye supported on the
composite of titanium oxide and zinc oxide nanoparticles, the
conversion efficiency was 33% and the fill factor was 0.1947.
[0022] In each of the above examples, the input power was
calculated from the known intensity of the lamp and illuminated
area of each solar panel, which was (1.times.2) cm.sup.2. From the
above, one can see that the energy conversion efficiency is highest
(67%) for the sample including just titanium oxide nanoparticles
(with the B. vulgaris subsp. cicla dye supported thereon), and
second highest (33%) for the composite of titanium oxide and zinc
oxide nanoparticles (with the B. vulgaris subsp. cicla dye
supported thereon). These are compared against the 2% conversion
efficiency of the control sample, which did not have the B.
vulgaris subsp. cicla dye.
[0023] It is to be understood that the present invention is not
limited to the embodiments described above, but encompasses any and
all embodiments within the scope of the following claims.
* * * * *